Apparatus for utilizing solar radiant energy



(No Model.)

B. WESTON.

APPARATUS FOR UTILIZING SOLAR RADIANT ENERGY. No. 889,124. Patented Sept. 4, 1888.

film/E8858: INVENTOR. M Q

P ATTORNEY.

N PUERS. Phuio-ulhognphcr, Washinglnn, n. c

, UNITED STATES PATENT OEEIcE.

EDWVARD WESTON, OF NEWARK, NEIV JERSEY.

APPARATUS FOR UTILIZING SOLAR RADIANT ENERGY.

SPECIFICATION forming part of Letters Patent No. 389,124, dated September 4, 1888.

Application filed October-17, 1887. Serial No. 252,514.

To aZZ whom it may concern:

Be it known that I, EDWARD \VESTON, of Newark, Essex county, New Jersey, have in vented a new and useful Improvement in Apparatus for Utilizing Solar RadiantEnergy, of which the following is a specification.

I propose to transform radiant energy derived from the sun into electrical energy, or through electrical energy into mechanical energy. I may directly employ the electrical energy so obtained, or I may convert it into mechanical energy prior to such utilization.

In order to carry my improvement in the aforesaid art into practical effect, I concentrate or converge the solar beam upon any electrogenerative apparatus which depends upon an increase of its temperature for the production of an electric current, or, in other words, which will yield electrical energy in a proportion to the increase of temperatures to which it is subjected. A thermoelectric element wherein two bodies of dissimilar metal are placed side by side united atone end,and everywhere elseinsulated from one another, is such an clcctro-generative apparatus. \Vhen several of such ele ments are joined in series, so that their alternate junctions lie near together and in one plane,sneh an arrangement is termed a thcr mopile. lf onejunctiou of a thermoelectric element or one set ofjunctious in a thermopile be heated to a fixed temperature and the other junction or set of junctions be maintained at a lower temperature, then an electrical current will be set up in a circuit including said dissimilar metal bodies, the electromotive force of which current in the thermopile will be the sum of the electro-motive forces of the currents produced by the several elements and will increase up to a maximum proportionately to the increase of temperature. I expose to the solar rays one set of the junctions of a thermopile. I thus cause an electrical current in a circuit including said thermopile. Inasmuch, however, as for practical purposes itis not expedient to construct the face ofa thermopile of very large area, I concentrate the solar beam upon the face of the thermopile by any known device for that purposesuch as converging mirror orlens so that relatively much higher temperature, and hence greater energy per unit of surface area, may be (No model.)

obtained. In order, fnrther,to produce absorp' tion of both heat and light energy, I cover the face of the thermopile with any absorbent materialsuch as lamp-blacl --or I may simply dull such surface, so that its capacity for reflecting light rays may be diminished as far as possible. The electrical current thus obtained I may accumulate in a storage or secondary battery; or I may conduct it directly to any form of electromotor wherein the electrical e11- ergy of said current is converted into mechanical energy.

In place of a thcrmopile I may employ any equivalent means for converting heat energy into electrical energy. So, also, as already stated, I may employ various means'for converging or concentrating the solar rays upon the electro-generative apparatus.

One mode of carrying my invention into practical effect is embodied in the apparatus illustrated in the accompanying electrical diagram, which, it will be understood, does not show exact proportions or details of construction.

The improvement in the art of utilizing solar radiant energy by converting the same into electrical cnergy,or through electrical energy into mechanical energy,Ido not herein claim, inasmuch as the same forms the subject of another application for Letters Patent of the United States filed by me simultaneously herewith, Serial No. 252,5 l5.

In the accompanying drawings, Figure 1 is a general diagrammatic view of an apparatus embodying my invention. Fig. 2 represents the heat-recciving surface of the thermopile in plan view.

Similar letters of reference indicate like parts.

Referring to said drawings, A represents a thermopile composed of bars B C, of dissimilar metals, joined at 1) and E.

F is a lens whereby the solar rays are conccntrated or converged upon the surface formed by thejnnctions D of said pile. Said surface may be covered with a light-absorbing material,G-. as lamp-blaelgsubstantially as indicated in Fig. 2, where a portion of said covering is represented as broken away, or be simply dulled or darkened, so as not to reflect light rays.

The thcrmopile A is connected by wires a a in circuit with the electrodes I J of the secondary cell E, and said electrodes are also connected by wires 1) b with the binding-posts of any form of electromotor, as K. Interposed in one of the wires 1) is an ordinary circuit-closer, 0, whereby circuit can be established or broken between the secondary cell II and motor K.

At d is an electrounagnet having its coil in circuit with one of the wires (1.. The armature c of said magnet is polarized. Said armature is pivoted atj', and is connected to one terminal of the magnet-coil, so that the circuit proeecds from'the coil through the armature to a stop, 9, wherewith the armature makes contact when attracted by the eleetro-magnet,and thence to the secondary cell H. A spiral spring, 71, attached to the pivoted armature, aids in retracting the same from the pole of the magnet.

When the current proceeds from the thermopile to the secondary cell, the magnet and the polarized armature mutually attract, and circuit to the secondary cell is maintained. When, however, the strength of the current in the cell becomes greater than that passing 'to the cell,then the magnet-poles are reversed,

and magnet and armature mutually repel, and circuit between cell and thcrmopile is broken. In thisway short-circuiting of the cell through the thermopile may be prevented. This arrangement of automatic circuit-closer I do not claim. I introduce it here merely as illustrative of known apparatus practically useful iior the purpose stated.

The object of the storage or secondary cell is to accumulate the solar radiant energy in the form of electrical energy, so that, for example, energy accumulated during hours of sunshine may be utilized during night or periods of cloudy weather; or, in other words, said cell here acts substantially as reservoir into which electrical energy may be intermittently delivered, but from which it may be taken as a constant supply.

I am well aware that various devices have been contrived for direct-1y utilizing solar heat to produce steam or hot air, or for measuring the intensity of solar radiation; but I am not aware that the utilization of the suns heat and light rays through the conversion of solar radiant energy into electrical energy or into mechanical energy through intermediate conversion into electrical energy has hitherto been accomplished.

I do not claim herein the combination of a thcrmopile, a means of converging solar rays thereupon, and an electric motor in circuit with said thermopile, for the reason that I intend to make that invention the sul;= ject-matter of another application for Letters Patent hereafter to be filed, and of this reservation I hereby give public notice.

I claim- 1. The combination of athermopile, ameans (such as a mirroror lens) arranged to conceir trate or converge solar rays thereupon, and a secondary or storage cell in circuit with said thermopile, substantially as described.

2. The combination of a thermopilc, a means (such as a mirror or lens}- arranged to concentrat'e or converge solar rays thereupon and in circuit with said thermopile, a secondary or storage cell,and an electromotor, substantially as described.

EDXVARD \VESTGN.

W i tn csses II. A. BEUKMEYER, E. 16. CARY. 

